风力发电机用特大型双排四点接触转盘球轴承力学分析及优化设计

发布时间：2018-01-11 21:32

本文关键词：风力发电机用特大型双排四点接触转盘球轴承力学分析及优化设计　出处：《河南科技大学》2014年硕士论文　论文类型：学位论文

【摘要】：特大型双排四点接触球轴承以其独特的结构特点被广泛用于风力发电机变桨系统中，其工作特性及可靠性直接影响整个风力发电机的正常运行。风力发电机特殊的使用环境要求变桨轴承具有长寿命、高可靠性及低摩擦力矩，，特大型双排四点接触球轴承的结构参数直接影响其载荷分布、寿命、承载能力及摩擦力矩。基于赫兹接触和摩擦学理论，对特大型双排四点接触球轴承力学性能、承载能力、疲劳寿命、油膜厚度、结构优化、摩擦力矩进行了分析。并使用风电变桨轴承模拟试验机进行了摩擦力矩的试验验证。首先根据特大型双排四点接触球轴承的结构特点及受载情况建立轴承的力学分析模型，使用ANSYS有限元分析软件分析了特大型双排四点接触球轴承最大接触应力，和数值计算结果进行了比较。根据Lundberg-Palmgren理论，给出了特大型双排四点接触球轴承疲劳寿命的计算方法。建立了特大型双排四点接触球轴承的摩擦力矩计算模型。并分析了轴承结构参数对特大型双排四点接触球轴承接触载荷分布、最大接触应力、疲劳寿命、承载能力、油膜厚度及摩擦力矩的影响。然后根据遗传算法理论对轴承参数进行优化。最后通过试验值和计算结果对比，验证力学模型及轴承摩擦力矩计算方法的正确性。结果表明：轴承结构参数影响轴承接触载荷分布、最大接触应力、轴承承载承载能力、轴承疲劳寿命、轴承最小油膜厚度及轴承摩擦力矩。随着轴承负游隙绝对值的增大，轴承最大接触应力及最大接触载荷先减小后增大；轴承原始接触角增大，轴承最大接触载荷及最大接触应力减小；轴承接触沟曲率半径系数增大，轴承最大接触载荷及最大接触应力增大。有限元计算轴承接触应力与数值计算方法进行比较，结果相差不大。轴承结构参数影响轴承承载能力，当轴承承受径向力为0kN时，轴承游隙对轴承承载能力影响较小；随着沟曲率半径系数增大，承载能力减小；原始接触角增大，轴承承载能力增大。随着轴承承受径向力增大，轴承游隙及轴承沟曲率半径系数对轴承承载能力的影响趋势相同。轴承原始接触角对轴承承载能力的影响趋势不同。随着轴承负游隙绝对值的增大轴承疲劳寿命先增大后减小，摩擦力矩减小。随着轴承沟曲率半径系数的增大轴承疲劳寿命减小，摩擦力矩减小。随着轴承负游隙绝对值、沟曲率半径系数、原始接触角增大，轴承最小油膜厚度先增大后减小。
[Abstract]:Super large double-row four-point contact ball bearings are widely used in wind turbine variable propeller system due to their unique structural characteristics. Its working characteristics and reliability directly affect the normal operation of the whole wind turbine. The special operating environment of the wind turbine requires long life, high reliability and low friction moment of the pitch bearing. The structural parameters of super large double row four point contact ball bearing have direct influence on its load distribution, life, bearing capacity and friction moment. Based on Hertz contact and tribology theory, the mechanical properties, bearing capacity, fatigue life, oil film thickness and structural optimization of super large double-row four-point contact ball bearings are optimized. The friction torque is analyzed, and the friction torque is verified by using wind power variable propeller bearing simulation test machine. Firstly, the mechanics of bearing is established according to the structure characteristic and load condition of super large double-row four-point contact ball bearing. Analytical model. The maximum contact stress of super large double-row four-point contact ball bearing is analyzed by using ANSYS finite element analysis software. The results are compared with the numerical results. According to the Lundberg-Palmgren theory. The calculation method of fatigue life of extra large double row four point contact ball bearing is given. The calculation model of friction moment of super large double row four point contact ball bearing is established. The bearing structure parameters are analyzed to the extra large double row four point contact bearing. Contact load distribution of ball bearings. The effects of maximum contact stress, fatigue life, bearing capacity, oil film thickness and friction torque on the bearing parameters are optimized based on genetic algorithm. Finally, the experimental results are compared with the calculated results. The correctness of the mechanical model and the calculation method of bearing friction moment is verified. The results show that the bearing structure parameters affect the bearing contact load distribution, maximum contact stress, bearing bearing capacity, bearing fatigue life. With the increase of the absolute value of negative clearance, the maximum contact stress and maximum contact load of bearing decrease first and then increase. With the increase of the original contact angle of the bearing, the maximum contact load and the maximum contact stress of the bearing decrease. The maximum contact load and maximum contact stress of the bearing are increased with the increase of the radius of curvature of the contact groove. The finite element method for calculating the contact stress of the bearing is compared with the numerical method. The results show that the bearing bearing capacity is influenced by bearing structural parameters, and when bearing bearing radial force is 0 KN, bearing clearance has little effect on bearing bearing capacity. With the increase of the radius of curvature, the bearing capacity decreases. The bearing bearing capacity increases with the increase of the original contact angle. The bearing bearing bearing clearance and radius of curvature coefficient influence trend is the same. Increase first, then decrease. With the increase of bearing groove radius coefficient, the fatigue life of bearing decreases, and the friction moment decreases. With the bearing negative clearance absolute value, groove curvature radius coefficient, the original contact angle increases. The minimum oil film thickness of bearing first increases and then decreases.
【学位授予单位】：河南科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM315;TH133.3

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